Engine accessory drive support

ABSTRACT

An optional accessory drive gear for an internal combustion engine is mounted within a gear housing on a two-piece support carried by a portion of an end plate spaced from the end of the engine block. The support includes a mounting plate secured to the engine end plate in the space between it and the block and a gear support member secured to the mounting plate. The support member includes a hub for supporting the accessory gear and a flange which is piloted within the end plate to provide for proper positioning of the gear. The two-piece support is arranged for ease of installation after engine assembly, the mounting plate being receivable in the space between the end plate and cylinder block and the gear support member being small enough to pass through an opening in the engine gear train housing which is provided for installation of the accessory drive gear.

United States Patent Wallace June 10, 1975 Primary Exurrzinercharles l. Myhre ENGINE ACCESSORY DRIVE SUPPORT Assistant Examiner-William C. Anderson [75] Inventor: Michael A. Wallace. Pontiac, Mich. Attorney Agem Ur Firm RObert L Ouuand [73) Assignee: General Motors Corporation. Detroit, MlCl'l. [22] Flled: 19, An optional accessory drive gear for an internal com- 2 APPL 7 2 3 bustion engine is mounted within a gear housing on a twopiece support carried by a portion of an end plate 5 need from the end of the en ine block. The su ort [52] 123/195 A: 123/[95 C iscludes a mounting plate secired to the engimf end [51 I 'l Fozf 7/00; Fozb 77/14 plate in the space between it and the block and a gear [58] held of March l23/195 R1 195 support member secured to the mounting plate. The

[23/198 E support member includes a hub for supporting the accessory gear and a flange which is piloted within the end plate to provide for proper positioning of the gear. References Cited The two-piece support is arranged for ease of installa- UNlTED STATES PATENTS tion after engine assembly, the mounting plate being 1.779.081. 10/1930 Davies 1. 123/195 A receivable Spac6 between the end Plate and 3.088446 5/1963 Fox et al. 123/195 A x inder block and the PP member being Small 3,]6Ll82 l2/l964 Alhinson et .11 .1 123/411 x n gh to p through an p g in the engine g 16061874 )IW'H Grcgory .i 123/195 A train housing which is provided for installation of the 3.6l6.7? 6 ll/l97l Hatz .1 l23/l95 A X accessory drive gegp 2 Claims, 6 Drawing Figures QC MO PATENTED JUN 1 0 I975 SPEET ENGINE ACCESSORY DRIVE SUPPORT FIELD OF THE INVENTION The present invention relates to internal combustion engines and more particularly to improved mounting means for supporting an optionally installed accessory drive gear in an engine, particularly of the industrial or heavy automotive type.

BACKGROUND OF THE INVENTION It is known in the art to provide internal combustion engines such as diesel engines for automotive and industrial purposes with gear trains for driving the camshafts and accessories operated by the engine. In many instances, provision is made for adding accessories which may be desired on an optional basis by the customer when an engine is sold or is in use. Such accessories include, for example, power steering, which may require an engine driven hydraulic pump.

In certain engine types, such as are shown in US. Pat. No. 3,161,182 Albinson et al, provision for optional engine accessories, such as a power steering pump, is made through the use of an optionally installed accessory drive gear. Such a gear may be mounted within a gear train and flywheel housing at the end of the engine and be connected with the remainder of the engine timing and accessory drive gear train.

In the past, some optional accessory drive gears of this type have been carried by a support member including a hub portion on which the gear is mounted and a flange portion which is secured to the engine end plate in the space between it and a stepped portion of the engine cylinder block. When the support is installed the auxiliary drive gear may easily be removed from the hub through an opening provided in the gear train housing on which the optional accessory is mounted. However, installation of the support member requires that the engine be partially disassembled by removal of the accessory drive housing and end plate so that the support member may be mounted on the end plate before it is reassembled to the engine. Thus, a substantial amount of labor is required to add such an accessory drive to an engine after it has been assembled. adding significantly to the cost of the new accessory.

SUMMARY OF THE INVENTION The present invention provides improved support means for an optional accessory drive gear in which the support is made as a two-piece assembly designed to be easily installed after the engine is fully assembled. The improved assembly includes a gear support member in the form of a flanged hub which supports the accessory drive gear and is piloted in the engine end plate for properly positioning the gear. This support member is made small enough to pass through the opening in the accessory drive housing provided for subsequent installation of the accessory drive gear.

The support member is retained in position by a separate mounting plate to which it is secured by bolts applied from the interior of the accessory drive housing. The mounting plate is in turn secured to the end plate within the space provided between it and the engine block. The mounting plate may be installed in this posi tion without disassembling the end plate from the block. Lubrication passages are provided in the mounting plate and support member to provide for an external supply of oil for lubricating the gear hub. Mating pilot means are utilized to properly orient the mounting plate and support member with respect to one another.

The improved arrangement permits greater flexibility in adding optional accessories to the engine after assembly and in subsequent field installations without adding substantially to the cost of such installations as compared to the cost of applying the components upon initial engine assembly.

These and other features and advantages of the invention will be more fully understood from the following description of a preferred embodiment of the invention taken together with the. accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings:

FIG. I is an end view of an internal combustion engine including accessory drive means according to the invention;

FIG. 2 is an enlarged view of a portion of the engine of FIG. 1 showing the application of the accessory drive means to the engine;

FIG. 3 is a longitudinal cross sectional view of the portion illustrated in FIG. 2 taken generally in the piane indicated by the line 3-3 of FIG. 2;

FIG. 4 is another longitudinal cross sectional view taken generally in the plane indicated by the line 44 of FIG. 2;

FIG. 5 is a fragmentary view showing the application of the mounting plate as viewed from the plane indicated by the line 55 of FIG. 3, and

FIG. 6 is a fragmentary longitudinal cross sectional view showing the mounting plate application and taken generally in the plane indicated by the line 6-6 of FIG. 5.

DESCRIPTION OF THE ILLUSTRATED EMBODIMENT Referring now to the drawings in detail, numeral 10 generally indicates an internal combustion engine, particularly a diesel engine ofthe type used for heavy automotive and industrial applications. Engine 10 includes a cylinder block 12 carrying the usual cylinders, not shown, and closed at their outer ends by a pair of cylinder heads 14, 16.

At one end of the engine an end plate 18 is mounted on the end of the cylinder block 12, as best illustrated in FIG. 3. The end plate 18 is utilized for mounting a timing and accessory drive train of gears driven by the engine crankshaft through means not shown. The gear train is used to drive the engine camshafts and governor, as well as other necessary devices, and is further available for use in driving optionally installed accessories.

The gear train as well as the engine flywheel, not shown, are enclosed by a housing 20 which is secured to the end plate I8 by means of bolts 22 or the like at various locations around its periphery. A gasket 24 is provided between the housing and end plate to prevent the escape of lubricating oil therebetween.

Housing 20 is provided in a portion near one edge with a flat mounting boss 26 on which various optional accessories, such as a power steering pump, may be mounted. A circular opening 28 is provided centrally of the boss through which a drive may extend to an internally mounted accessory drive gear, shown in phantom in FIG. 3 and indicated by numeral 30. Opening 28 is sized sufficiently large so that gear 30 may be installed therethrough.

Accessory drive gear 30 is carried on the end plate 18 by a support assembly generally indicated by numeral 32. The cylinder block 12 is longitudinally stepped near its edge so as to provide a clearance space 34 between the end plate 18 and the end wall 36 of the block. In addition, a cylindrical opening 38 is provided in the end plate 18 in axial alignment with the opening 28 and of about the same diameter.

Support assembly 32 includes two major elements, a hub-like gear support member 40 and a mounting plate 42. Support member 40 includes a radial flange portion 44 which is received and piloted in the circular opening 28 in the end plate 18. A hub portion 46 extends axially outwardly from the flange portion 44 and provides means on which the gear 30 may be rotatably mounted. The support member further includes a protruding pilot 48 extending from the flange portion in a direction opposite from the hub portion 46. Pilot 48 has an annular external pilot diameter 50 for mating with the mounting plate, as will be subsequently described.

Flange 44 includes a plurality of spaced arcuate pilot portions 52 interrupted by flattened portions 54 so as to narrow the overall width of the flange sufficiently to provide for installation of the support member 40 within the housing through the opening 28 provided therein.

The mounting plate 42 is made sufflciently thin to fit within the clearance space 34 provided between cylinder block 12 and the end plate 18 and includes a circular recess 56 in which the pilot portion 48 of the support member is received. Recess 56 includes an internal annular pilot diameter 58 which engages the external pilot diameter 50 so as to properly position the elements 40. 42 of the support means with respect to one another.

The mounting plate 42 is secured to the end plate 18 by a plurality of bolts of various types. These include a pair of short bolts 60 which are assembled from within the clearance space between the end plate 18 and the block 12 and extend through openings 62 in the mounting plate to threadably engage press nuts 64 fixed in openings 66 in the end plate 18. These short bolts 60 are utilized in locations adjacent the point of engagement of the accessory drive gear with the remainder of the gear train to provide an open space in the housing and avoid interference with the gear engagement.

In addition, a plurality of long bolts are utilized in the assembly which extend through openings in the walls of the accessory drive housing 20 and through the end plate 18. In the embodiment shown, three of these long bolts 68 are received within threaded openings 70 provided in the mounting plate 42, while the remaining long bolt 72 extends through the plate 42 and is secured thereto by a nut 74.

The support member 40 is in turn secured to the mounting plate 42 by means of six bolts or screws 76. These bolts 76 are inserted from the interior of the housing 16 and extend through spaced openings in the support member flanged portion into engagement with the threaded edges of openings 78 provided in the mounting plate.

The support member is provided with oil passages 80 and 82 which extend interiorly from the outer surface of the hub portion 46 on which the gear is mounted through the end of the protrusion 48 which is received within the recess 56 of the mounting plate. These passages connect with continuing oil passages 84 and 86 provided in the mounting plate and extending from the recess 56 to the outer edge of the plate. There, passage 86 connects through a fitting 88 and conduit 90 with the engine lubricating oil system in the block 12. A gasket 92 is provided between the mounting plate 42 and the end plate 18 to prevent loss of lubricating oil between these components.

The present invention has the advantage that the ap plication of an optional engine driven accessory, such as a power steering pump, to an engine of the type de scribed after it has been assembled, may be accomplished quite simply and without disassembling any major components of the engine. Such application of the accessory drive may be accomplished merely by removing the cover plates normally provided over the openings 28 and 38 in the housing and end plate l6, l8 and securing the mounting plate 42 to the end plate 18 in the space provided between it and the cylinder block. At the same time, the support member 40 is installed through the opening 28 and fitted with its flange piloted within the opening 38 of the end plate and its pilot 48 within the recess 56 of the mounting plate. if necessary, the mounting plate bolts may be loosened so that the proper alignment is obtained. It should be understood that the piloting of the flange of the support member directly within the engine end plate is desirable to minimize tolerance stack-up and provide for proper positioning of the subsequently applied accessory drive gear 30 with respect to the connecting gears of the engine accessory drive train.

While the invention has been described by reference to a specific embodiment, it should be understood that changes may be made by those skilled in the art within the scope of the inventive concepts disclosed. Accordingly, it is intended that the invention not be limited, except by the language of the following claims.

What is claimed is:

1. In combination, an internal combustion engine including accessory drive means and comprising an engine block assembly having an end plate mounted on one end of said block, said end plate having an accessory drive mounting portion adjacent one edge of said block, and including an opening for receiving accessory drive gear support means, said block being stepped longitudinally adjacent said drive mounting portion so as to provide a limited space between said end plate and said block adjacent said portion and open on at least one side thereof,

a gear housing mounted on said end plate and defining therewith an enclosure for an engine timing and accessory drive gear train, said gear housing having an opening axially aligned with said end plate opening, said gear housing opening being adapted to permit installation of an optional accessory drive gear in said gear train without requiring removal of said gear housing,

a gear support member having a flange portion and a hub portion extending axially from said flange portion, said hub portion being adapted to receive such accessory drive gear for rotation thereon and including oil passage means extending to the surface of said hub portion to supply oil for lubricating such gear, said flange portion being received and piloted within said end plate opening to position said hub and such accessory drive gear with respect to said gear train, said support member further including a protruding pilot extending axially from said flange portion in the direction opposite said hub portion, said pilot including an external annular pilot diameter and said oil passage means extending through said support member to the end of said pilot,

a support mounting plate disposed in the space between said engine block and said end plate, said mounting plate including a circular recess having an annular internal pilot diameter engaging and piloted on said support member pilot, said mounting plate including oil passage means extending from said recess to an outer edge of said plate and connecting with said support member oil passage means to provide for the supply of oil thereto from an external source,

first means securing said mounting plate to said end plate, and

second means securing said support member to said mounting plate,

said mounting plate being sufficiently thin to permit installation in or removal from its location between said block and end plate without removing said end plate from said block, said support member flange width being smaller than said gear housing opening so as to permit installation or removal of said support member through said gear housing opening without removal of said gear housing from said end plate.

2. The combination of claim 1 wherein said first securing means includes at least one short bolt insertable through an opening in said mounting plate from the space between said block and said end plate and en gageable with threaded means secured in said end plate so as to provide an open area adjacent said support member for connection of such accessory drive gear with said gear train, said first securing means further comprising a plurality of long bolts inserted from the housing side of said end plate through openings in the side walls of said housing member and aligned openings in said end plate into engagement with threaded openings in said mounting plate, and

said second securing means comprises a plurality of bolts extending from within said housing member through the flange portion of said support member and engaging threaded openings provided in said mounting plate. 

1. In combination, an internal combustion engine including accessory drive means and comprising an engine block assembly having an end plate mounted on one end of said block, said end plate having an accessory drive mounting portion adjacent one edge of said block, and including an opening for receiving accessory drive gear support means, said block being stepped longitudinally adjacent said drive mounting portion so as to provide a limited space between said end plate and said block adjacent said portion and open on at least one side thereof, a gear housing mounted on said end plate and defining therewith an enclosure for an engine timing and accessory drive gear train, said gear housing having an opening axially aligned with said end plate opening, said gear housing opening being adapted to permit installation of an optional accessory drive gear in said gear train without requiring removal of said gear housing, a gear support member having a flange portion and a hub portion extending axially from said flange portion, said hub portion being adapted to receive such accessory drive gear for rotation thereon and including oil passage means extending to the surface of said hub portion to supply oil for lubricating such gear, said flange portion being received and piloted within said end plate opening to position said hub and such accessory drive gear with respect to said gear train, said support member further including a protruding pilot extending axially from said flange portion in the direction opposite said hub portion, said pilot including an external annular pilot diameter and said oil passage means extending through said support member to the end of said pilot, a support mounting plate disposed in the space between said engine block and said end plate, said mounting plate including a circular recess having an annular internal pilot diameter engaging and piloted on said support member pilot, said mounting plate including oil passage means extending from said recess to an outer edge of said plate and connecting with said support member oil passage means to provide for the supply of oil thereto from an external source, first means securing said mounting plate to said end plate, and second means securing said support member to said mounting plate, said mounting plate being sufficiently thin to permit installation in or removal from its location between said block and end plate without removing said end plate from said block, said support member flange width being smaller than said gear housing opening so as to permit installation or removal of said support member through said gear housing opening without removal of said gear housing from said end plate.
 2. The combination of claim 1 wherein said first securing means includEs at least one short bolt insertable through an opening in said mounting plate from the space between said block and said end plate and engageable with threaded means secured in said end plate so as to provide an open area adjacent said support member for connection of such accessory drive gear with said gear train, said first securing means further comprising a plurality of long bolts inserted from the housing side of said end plate through openings in the side walls of said housing member and aligned openings in said end plate into engagement with threaded openings in said mounting plate, and said second securing means comprises a plurality of bolts extending from within said housing member through the flange portion of said support member and engaging threaded openings provided in said mounting plate. 